California Firm Doubles Flying Time of Jetpack

This futuristic way of getting around, made famous by the '70s kiddie show "Ark II" and the 1991 Disney movie "The Rocketeer," has actually been around for 50-odd years. A precursor was even developed by the Germans during World War II.

But it's always had one big problem: There's only so much rocket fuel a man can carry strapped to his back, and that amount tends to run out pretty quickly — in about 30 to 40 seconds.